Floating diaphragm



Jan. 28, 1969 A. J. wlLTsHlRE 3,424,335

FLOATING DIAPHRAGM med July 25, 196e sheet INVENTOR. L ARTHUR J.W|LTSH|RE ATTORNEYS Jn- 28, 1969 A. J. WILTSHIRE 3,424,335

' FLOATING DIAPHRAGM Sheet 2 012 Filed July 25, 1966 F|G 5 v INVENTOR.

ARTHUR J.w|LTsH|RE IM/AAA United States Patent O 3,424,335 FLOA'IING DIAPHRAGM Arthur J. Wiltshire, Cleveland, Ohio, assignor to Structural Fibers, Inc., Chardon, Ohio, a corporation of Ohio Filed lIuly 25, 1966, Ser. No. 567,433

U.S. Cl. 220-26 10 Claims Int. Cl. B65d 87 /20 ABSTRACT OF THE DISCLOSURE A floating diaphragm for separating liquid and gaseous substances within a tank or container having a relatively Small access opening therein as compared to the diameter of the diaphragm and the `diameter of the container, and a method of assembling the diaphragm within such a tank or container. The diaphragm includes two sheets of the flexible material joined together at spaced concentric circles. Two such circles dene an annular sleeve which receives a buoyant tube. The tube is inserted through an opening in the sleeve. The buoyant tube may be inserted in the sleeve after the thin, flexible material has been inserted into the tank or container through the relatively small access opening. Male plugs `and female sockets at the ends of the buoyant tube rigidly mate the free ends of the buoyant tube within the annular sleeve.

This invention relates to a diaphragm for separating liquid and gaseous substances within a tank and, more particularly, to a floating diaphragm which may be partially assembled within a tank or container having a relatively small opening therein.

In many applications, such as home water pump systems, it is desirable to provide a floating diaphragm within a tank which separa-tes pressurized liquid and gaseous substances within the tank. Suitable diaphragms for this purpose may easily be fabricated and then installed within the tank if the tank has a relatively large mouth or a separable top cover portion. However, many home water systems in use today employ one-piece tanks having a relatively small access opening, which necessitates the insertion of a floating diaphragm within the tank after the tank has been manufactured.

Various diaphragm oats have been proposed for tanks having narrow openings and such diaphragms generally include a flexible base member having an outer periphery which conforms to the interior cross sectional configuration of the'tank within which it is inserted. Such diaphragms also include a floatable material on the base portion. The floatable material is provided with discontinuities so that the base may be folded for insertion into the narrow tank opening. Such discontinuities in the oatable material, however, permit the liquid to flow over the periphery of the base member and through the discontinuities in the oatable material, thus minimizing the effectiveness of the diaphragm as a separating means. The use of a relatively ilexible buoyant material to serve as a floating means for the base members has not been entirely successful, since such material tends to be crushed when the tank is pressurized.

The present invention overcomes many of the -di'iculties inherent in prior art diaphragm float constructions by providing a diaphragm structure which substantially elimina-tes liquid seepage over the diaphragm by providing a continuous curbing means adjacent the periphery of the diaphragm.

It is an object of the present invention to provide a diaphragm for separating liquid and gaseous substances within a tank which has a continuous curbing means of buoyant material 4at its periphery and which may be partially assembled outside of a tank and which may be 3,424,335 Patented Jan. 28, 1969 ice finally assembled within the tank through a relatively narrow opening.

It is a further object of this invention to provide a diaphragm for separating liquid and gaseous substances within a tank which has an axial standpipe therethrough.

It is a further object of this invention to provide a diaphragm for separating liquid and gaseous substances within a tank which may move axially within the tank as the liquid level varies without binding on the sidewalls of the tank or on a standpipe which may be provided within the tank.

These and other objects, advantages, and features of the invention will become more apparent and more readily understood from the following detailed description and from the accompanying drawings.

In the drawings:

FIG. 1 is a partially schematic, vertical cross sectional view of a diaphragm float according to one aspect of this invention, showing the oat installed within a tank having a standpipe therein;

FIG. 2 is a plan view of a diaphragm float according to one aspect of this invention, with portions of the float broken away for clarity;

FIG. 3 is a cross sectional view of the float illustrated in FIG. 2, the plane of the section lbeing indicated by the line 3 3 in FIG. 2;

FIG. 4 is a partially schematic view of a diaphragm float according to another aspect of this invention, showing the float installed within a tank; and

FIG. 5 is a cross sectional View of the diaphragm float illustrated schematically in FIG. 4.

Referring now to the drawings, and particularly to FIGS. 1, 2, and 3, a floating diaphragm 10 according to one aspect of this invention is illustrated. As may be seen in FIG. 1, the floating diaphragm 10 is employed to separate water and air within a pressure vessel 11, which pressure vessel 11 comprises one unit of a home water system. The pressure vessel 11 may be fabricated from liber-reinforced plastic and have a cylindrical sidewall 12 `and integral oblate, ellipsoidal, top and bottom end portions 13 and 14 respectively. The bottom end portion 14 is provided with a foot structure 15 to support the tank and the top end portion 13 has `a relatively small axial opening 16 therein. A pump assembly 17 is mounted on the end -portion 13 and is provided with a downwardly and axially extending standpipe 18 which projects into the tank 11 through the opening 16 to a level which is in closely spaced adjacency to the bottom of the tank.

The oating diaphragm 10 comprises a thin, flexible membrane 19 which may be formed by two sheets of l2- mil vinyl 20 and 21 which are heat sealed in face-toface relationship at a plurality of concentric heat sealing zones 22, 23, 24, and 25. The heat sealed zones 22-25 may be provided by pressing the face-to-face vinyl sheets 20 and 21 with concentrically arranged heat sealing elements. An annular pocket 26 is defined by the heat sealed zones 22 and 23 and the pocket 26 encases an endless band 27 of buoyant material which is substantially incompressible under uniformly applied pressure. The band 27 may comprise two semicircular lengths 28 and 29 of hollow, rigid plastic tubing. In the illustrated embodiment, the plastic tubing may have an outside diameter of .840 inch and a wall thickness of .050 inch. Each length 28 and 29 is provided with a male plug member 30 which seals one end of the length of tubing and a complementary female socket member 31 which seals the other end of the length of tubing. Each male plug member 30 is received within the female socket member 31 of the other length of plastic tubing to form a continuous band of buoyant material.

The diaphragm 19 is provided with an annular float 32 which comprises top and bottom rings 33 and 34 which are cemented to the sheets 20 and 21 respectively. The rings 33 and 34 may be formed from rigid cell polyurethane foam having a density of 3 to 4 pounds per cubic foot.

The diaphragm 19 is provided with an aperture 35 which has an inside diameter which is slightly greater than the outside diameter of the standpipe 18. The endless band 27 is installed within its pocket 26 and the diaphragm 19 is installed within the tank 11 in the following manner. The diaphragm 19 is folded or rolled about its attached rings 33 and 34 so that it may be inserted through the opening 16 in the tank 11 together with the rings 33 and 34. The installer does not release the diaphragm 19 after it has been inserted through the opening 16, but retains a grasp on a portion of the periphery of the diaphragm 19. The installer then inserts one end of one of the lengths of tubing 28 and 29 into an opening 36 which is cut into the pocket 26 from the periphery of the diaphragm 19. If the installer has selected the length of tubing 29 and has inserted the end of that tubing having the female socket into the opening 36, he pushes the tubing through the pocket 26 until the male plug member is inserted within the opening 36. The installer thus has inserted one-half of the endless band 27 within the pocket 26.

The installer then continues to grasp the periphery of the diaphragm 19 and inserts the length 28 of tubing into the opening 36 so that the length of tubing 28 traverses the unfilled portion of the pocket 26. Since the installer has already inserted the female socket end of the length 28 into the opening, he inserts the male plug portion of the length 29 into the empty portion of the pocket 26 through the opening 36 so that the male plug portion 30 of the length 29 meets the female socket portion 31 of the length 28 at a point which is diametrically opposite the opening 36. The installer then joins the female socket of the length 29 with the male plug 30 of the length 28 at the opening 36. While still retaining his grasp on the periphery of the diaphragm 19, the installer moves the diaphragm 19 by his fingers until the abutting but unjoined portions of the band 27 are within his grasp. The installer then pushes those unjoined portions of the band 27 together through the pocket 26 until the male plug 30 snaps within the female socket 31. The installer may then release his grasp on the diaphragm 19.

The tank assembly may then be completed by installing the standpipe through the opening 35, closing the opening 16 in the tank 11, and installing the pump assembly 17 on the top portion 13 of the tank. The fluid is then admitted to the tank and the tank is pressurized to a pressure of, for example, 2O to 70 p.s.i. gauge.

With fluctuations in the level of uid within the tank 11, the diaphragm will uctuate with this level. As the opening 35 moves along the standpipe 18, the float 32 minimizes any tendency of the diaphragm 19 to be immersed in the fluid if the opening 35 should tend to drag along the standpipe 18. Any tendency of the opening 35 to drag along the standpipe 18 is minimized, however, by an annular lip 37 which is defined by the opening 35 and the radially inner surface of the float 32. Any fluid that may tend to ow through the opening 35 is confined between the standpipe 18 and the inner surface of the float 32.

The outer periphery of the tank float 10 comprises an annular lip 38. The annular lip 38 rides along the inner sidewall of the tank 11 and compensates for any surface irregularities in the tank sidewall. Some fluid may tend to collect on the top surface of the lip 38, but this iluid will be confined to that small area, since the endless band 27 and the upper surface of the pocket 26 comprise curbing means to prevent ow of the fluid over the entire top surface of the diaphragm 19. It should be appreciated that the endless band 27 will be in contact with the fluid, since such fluid is admitted through the opening 36 in the pocket 26. Further inward flow of the fluid is, of course, prevented by the heat sealed area 23.

Referring now to FIGS. 4 and 5, a floating diaphragm 50 according to a further aspect of this invention is illustrated. The diaphragm 50 is illustrated in FIG. 4 as an isolating means for separating liquid and gaseous substances within a tank 51. The tank 51 is similar to the tank 11, except that the tank 51 is closed at the top, is not provided with a standpipe, and the liquid is pumped into and out of the bottom fitting 51a which is threaded into an opening 51b.

The diaphragm 50 comprises two sheets of lZ-mil plastic heat sealed together in face-to-face relationship at concentric heat sealing zones 52, 53, and 54. The heat sealed zones 52 and 53 define an annular pocket 55 within which an endless band 56 is provided. The endless band 56 may comprise two semicircular lengths of plastic tubing which are joined together by male and female members (not shown but similar to the male and female members 30 and 31.)

The diaphragm 50 is inserted within the tank S1 in a manner similar to the insertion of the diaphragm 10 within the tank 11 by feeding the length of tubing through an opening 57 in the pocket 55. A small opening 58 is provided at the center of the diaphragm 50 to prevent air from being trapped beneath the diaphragm. If air were trapped beneath the diaphragm 50, the diaphragm would tend to be buckled when the tank 51 is pressurized.

The diaphragm 50 tends to ride on the surface of the liquid and any liquid that may tend to flow over a circumferential lip 50 at the periphery of the diaphragm 50 is isolated by curbing means which comprises the endless band 56 and the upper portion of the pocket 55.

What is claimed is:

1. A diaphragm for separating liquid and gaseous substances within a tank comprising a thin, flexible membrane having means defining an annular chamber adjacent the outer peripheral edge of said membrane, means delining an opening into said annular chamber, curbing means within said annular chamber, said curbing means comprising an annulus of buoyant material having a substantially uniform cross section with a vertical thickness sufficient to extend a substantial distance above the central portion of the membrane and being substantially incompressible under uniformly applied pressure, said annulus being formed by at least two arcuate sections connected together at their ends by rigid coupling means, whereby all portions of the substantially uniform cross section of the annulus will prevent the flow of fluid over the annulus and onto the top surface of said membrane.

2. A diaphragm according to claim 1 wherein said arcuate sections comprise hollow tubing.

3. A diaphragm according to claim 1 wherein said curbing means comprises an annulus formed by two substantially semicircular, hollow tubes which are connected to each other by said rigid coupling means.

4. A diaphragm according to claim 1 wherein said membrane extends beyond the curbing means to form a lip.

5. A diaphragm for separating liquid and gaseous substances within a tank, comprising two sheets of thin, flexible material joined together at spaced concentric zones, two of said zones defining an annular chamber therebetween, means defining an opening into said chamber, curbing means within said annular chamber, said curbing means comprising an annulus formed by two arcuate sections having a substantially uniform cross section with a vertical thickness sufficient to extend a substantial distance above the central portion of the membrane and being connected together by rigid coupling means, said sections being substantially incompressible under uniformly applied pressure, whereby all portions of the substantially uniform cross section of the annulus will prevent the flow of uid over the arcuate sections and onto the top of said membrane.

6. A diaphragm according to claim 5 wherein said arcuate sections comprise hollow tubing.

7. A diaphragm according to claim 5 wherein said sheets extend beyond the annular chamber to form a lip.

8. A method of assembling a diaphragm within a tank having a relatively small access opening therein, comprising the steps of providing a thin, flexible membrane having means delining an annular chamber adjacent the outer peripheral edge of said membrane, providing an opening into said chamber, inserting a major portion of said membrane into said tank through said access opening, and inserting curbing means Within said annular chamber by providing at least two substantially incompressible arcuate sections and inserting the arcuate sections within said annular chamber through said opening and coupling said arcuate sections together with rigid coupling means to form a continuous band.

9. The method according to claim 8 wherein said arcuate sections comprise non-collapsible hollow tubing.

10. A method of assembling a diaphragm within a tank having a relatively small access opening for. separating liquid and gaseous substances within the tank, comprising the steps of providing two sheets of thin, exible material, joining together said sheets in face-to-face relationship at spaced concentric zones so that two of said zones define an annular chamber therebetween, providing lan opening into said chamber, inserting the joined sheets into said tank through the access opening of the tank, and inserting curbing means having a substantially uniform cross section with a vertical thickness suflicient to extend a substantial distance above the central portion of the membrane within said annular chamber through said opening, said curbing means comprising an annulus formed by two substantially .noncollapsible semicircular hollow tubes joined at their ends to each other to form said annulus.

References Cited UNITED STATES PATENTS 2,461,537 2/ 1949 Field 220-26 2,847,142 8/1958 McClintock et al. 200-26 3,049,261 8/ 1962 Wade et al. 220-26 3,159,301 12/ 1964 Anderson 220--26 3,343,708 9/1967 Haas 220-26 3,253,732 5/1966 Dempster 220--26 JAMES R. GARRETT, Primary Examiner. 

